A known sensor device is described in Applicant's DE 32 15 212 A1, for example. The sensor device is in the shape of a rod, which is conventional, and comprises a sensor in the sensor head, the sensor being designed to detect the rotational movement of a rotor. For this purpose, this known sensor device is clamped in a retaining opening disposed in the region of the wheel by a separate clamping bush. The retaining opening is a hole or a bore, into which the clamping bush is slid.
The sensor device is installed by sliding the sensor device into the clamping bush up to the point of contact with the rotor and the sensor device being retained in the clamping bush by frictional force. The sensor device is axially displaceable in the clamping bush, however, protecting against damage to the sensor device during contra-rotation of the rotor, while nevertheless retaining the device in the clamping bush.
The known rod sensor is typically cylindrical and has a closed lateral surface. The sensor for detecting the wheel speed is retained in the interior of the lateral surface by a potting compound.
Elevated radiant heat is carried to the sensor within the sensor installation space, in particular during and after braking. This radiant heat can occur briefly or can persist for a relatively long time. Such temperature fluctuations can unfavorably affect the retaining forces of the rod sensor within the clamping bush such that the sensor device can migrate within the clamping bush, whereby the air gap between the sensor head and the rotor can increase, which is undesirable.
Furthermore, such sensor devices are mass-produced. It is desirable to minimize production costs.